CN104511720B - Reducing production method of deepwater submerged arc welding large-caliber steel pipes - Google Patents
Reducing production method of deepwater submerged arc welding large-caliber steel pipes Download PDFInfo
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- CN104511720B CN104511720B CN201310449665.6A CN201310449665A CN104511720B CN 104511720 B CN104511720 B CN 104511720B CN 201310449665 A CN201310449665 A CN 201310449665A CN 104511720 B CN104511720 B CN 104511720B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C37/00—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
- B21C37/06—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape of tubes or metal hoses; Combined procedures for making tubes, e.g. for making multi-wall tubes
- B21C37/08—Making tubes with welded or soldered seams
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Abstract
The invention discloses a reducing production method of deepwater submerged arc welding large-caliber steel pipes. In order to overcome the defects of reduction of the compression strength and incapability of satisfying the bruising pressure performance requirements of deepwater pipelines in a traditional JCOE process for producing thick-wall steel pipes, the method comprises such process steps as edge milling, edge pre-bending, JCO molding, joint closing and prewelding, inner welding, outer welding, mechanical reducing, quality checking, water pressure test, quality checking and chamfering, wherein the mechanical reducing is to perform the annular compression for the whole lengths of the steel pipes by a steel pipe sizing press. The method has the following beneficial effects: the steel pipe sizing press is used for annularly compressing the full lengths of the steel pipes, so that the steel pipes are locally deformed, the diameters of the pipes are decreased, and the size tolerances of the steel pipes are improved; because of the mechanical reducing, the residual stress is reduced, the straightness of the steel pipes is improved, the cold molding process of the steel pipes is optimized, and the compression yield strength and the bruising pressure of the steel pipes are improved; and all technical parameters of the steel pipes accord with the deepwater pipeline requirements through strict technical control.
Description
Technical field
The present invention relates to a kind of submerged-arc welding large-diameter steel pipe manufacturing method, especially relate to a kind of big mouth of deep water submerged-arc welding
The undergauge manufacture method of footpath steel pipe.
Background technology
At present the deepwater field of exploitation is generally in the depth of water 2000～3000m waters, and drilling well waters the deepest and adopting
The oil well depth of water has reached more than 6000m it is contemplated that by 2015, deepwater oilfield yield will account for the 25% of all seas yield, ocean sky
So the yield of gas will continue to increase, and will be eventually reached the 50% about of global gas production, this will make natural gas basis set
The investment applied increases, and in natural gas infrastructure construction, the quantity of required submerged pipeline will be significantly increased.
Over nearly 20 years, jcoe(heavy caliber straight-seam double-sided submerged-arc welding steel pipe moulding process) except the life for continental line pipe
Produce, be also gradually available for the production of big wall thickness Submarine linepipe.Pipelines in deep sea is under the high pressure of ambient water, and in pipeline
It is easily bent when laying.In order to avoid pipeline conquassation, need using relatively low radius-thickness ratio (d/t).In addition to wall thickness, steel pipe is justified
Degree is the direct factor that welding is docked in impact job site, and the steel pipe that circularity is good, caliber is uniform, under high discharge pressure
All directions stress equalization during military service, is the important leverage of pipeline quality.Particularly deepwater pipelines, major design load is outer
Pressure, related limit state is conquassation state it is desirable to steel pipe has high reliability, good circularity and uniform mechanical property
Energy.
" a kind of seabed is with x65 pipeline steel submerged arc straight weld pipe manufacturer for Chinese invention patent disclosed in 11 days January in 2012
Method " (cncn102310119a), the process for making of steel pipe include milling side, pre-flanging, jco molding, prewelding, interior weldering, outside weld,
First time ultrasound investigation, the inspection of first time x-ray, machinery expanding, the water pressure test, chamfered edge, retaining wall on slope, second ultrasound wave
Inspection, second x-ray inspection, pipe end magnetic particle inspection and presentation quality inspection.This invention makes a diameter of φ of x65 grade of steel
762mm, wall thickness be 28.6～30.2mm straight-line joint submerged arc welding tube in jco forming process each several part deformation uniformly, performance uniform；Solution
The steel pipe local heating in welding process that determined leads to the serious problem reducing of obdurability and elongation percentage；Solve steel pipe in machinery
Because processing hardening leads to the problem of intensity increase, toughness and uniform elongation reduction when expanding.
Although existing jcoe technique can produce the thick walled steel tube that circularity is less than 0.15%, its collapse pressure is significantly low
In the seamless steel pipe of identical grade of steel and radius-thickness ratio, because cold forming (particularly expanding operation) can lead to the collapse pressure of steel pipe to reduce
More than 30%.In short, due to Bauschinger effect, the expanding tensile strength raising making tube material along the circumferential direction, and make compression
Intensity decreases are it is impossible to meet the performance requirement of deepwater pipelines.
Content of the invention
In order to overcome existing reduction using the compressive strength that jcoe technique productions thick walled steel tube exists to use it is impossible to meet deep water
The deficiency of pipeline collapse pressure performance requirement, the present invention provides a kind of undergauge manufacturer of deep water submerged-arc welding large-diameter steel pipe
Method.
The technical solution adopted for the present invention to solve the technical problems is: the undergauge system of deep water submerged-arc welding large-diameter steel pipe
Make method, including side, pre-flanging, jco molding, joint close and prewelding, interior weldering, outside weld, the water pressure test, to rib, ultrasound investigation,
X-ray checks processing step, and concrete technology step is:
1) milling side, retaining wall on slope: two-sided milling is carried out to steel plate two edges by edge milling machines, makes up to the plate of requirement
Width, the edges of boards depth of parallelism and bevel shape；
2) pre-flanging: required according to steel pipe curvature and caliber size requires, edges of boards are bent to meeting using pre-flanging machine
The curvature requiring；
3) jco molding:
First, using jco forming machine, the half of the steel plate after pre-flanging is carried out Multi-step forming, be pressed into " j " shape；
By it, second half carries out same Multi-step forming again, is pressed into " c " shape；
The last middle pressing one-time in whole steel plate forms it into " o " shape of opening；
4) joint close and prewelding: by adjusting the position of joint close Prewelding machine pressure roller, make the bevel for welding of steel pipe after molding good
Coupling together it is ensured that misalignment, gap size meet the requirements, welded using gas shielded welding mode simultaneously；
5) weldering in: welded using four Lincoln weld bevel for weldings inside steel pipe, first adopts direct current anti-
Connect, the second to four is exchange；
6) outside weld: welded using four Lincoln weld bevel for weldings outside steel pipe, first adopts direct current anti-
Connect, the second to four is exchange；
7) mechanical undergauge: ring compression is carried out to steel pipe total length using plug press；
8) quality examination: ultrasound investigation, x-ray inspection, pipe end magnetic particle inspection and visual examination；
9) water pressure test: steel pipe is carried out with 100% hydrostatic test；
10) quality examination: ultrasound investigation, x-ray inspection, pipe end magnetic particle inspection and visual examination；
11) chamfered edge: the steel pipe checking qualified is carried out tube end maching.
Step 7) machinery undergauge, the main frame using plug press is four beam and four-post hydraulic machine pressing machines, and being equipped with front and back can
The rollgang of lifting and liftable rotating roller, during undergauge operation: by moved cross beam under main frame and roller-way coordination, look for
Go out the long axis direction of steel pipe oval cross section, and so that it is rotated to vertical direction, send into necking down mould paragraph by paragraph, make circle under pressure
Degree error ＜ 0.3%；Find out high point along steel pipe axis, and so that it is rotated to vertically upward, making high point be admitted to plug
Immediately below mould on press, steel pipe falls on bearing, improves steel pipe linearity, reach on plug press under molding pressure effect
Design requirement.
The measurement of step 7) diameter is carried out in the Difference angles away from weld seam, respectively ± [8,30,60,90,120,
150、172]°；The circularity recording after undergauge is between 0.10%～0.15%.
The testing pressure for hydrostatic test of step 9) is the 95%～100% of steel pipe SMYS.
The invention has the beneficial effects as follows, using plug press, ring compression is carried out to steel pipe total length so as to generation office
Portion deforms, and reduces caliber, improves steel pipe sizes tolerance；By mechanical necking down, reduce residual stress, improve the linearity of steel pipe,
Optimize steel pipe cooling formation technic, improve compression yield strength and the collapse pressure of steel pipe, by strict technical controlling, make steel
Every technical parameter of pipe meets deepwater pipelines and requires.
Specific embodiment
With reference to embodiment, the invention will be further described.But, those skilled in the art it should also be understood that this
Invention is not limited to listed specific embodiment, as long as meeting the spirit of the present invention, all should be included in the protection of the present invention
In the range of.
The deep water of the present invention undergauge manufacture method of submerged-arc welding large-diameter steel pipe, concrete technology step is:
1) milling side, retaining wall on slope: two-sided milling is carried out to steel plate two edges by edge milling machines, makes up to the plate of requirement
Width, the edges of boards depth of parallelism and bevel shape.
2) pre-flanging: required according to steel pipe curvature and caliber size requires, edges of boards are bent to meeting using pre-flanging machine
The curvature requiring.
3) jco molding.
First, using jco forming machine, the half of the steel plate after pre-flanging is carried out Multi-step forming, be pressed into " j " shape；
By it, second half carries out same Multi-step forming again, is pressed into " c " shape；
The last middle pressing one-time in whole steel plate forms it into " o " shape of opening.
4) joint close and prewelding: by adjusting the position of joint close Prewelding machine pressure roller, make the bevel for welding of steel pipe after molding good
Coupling together it is ensured that misalignment, gap size meet the requirements, welded using gas shielded welding mode simultaneously.
5) weldering in: welded using four Lincoln weld bevel for weldings inside steel pipe, first adopts direct current anti-
Connect, the second to four is exchange.
6) outside weld: welded using four Lincoln weld bevel for weldings outside steel pipe, first adopts direct current anti-
Connect, the second to four is exchange.
7) mechanical undergauge: ring compression is carried out to steel pipe total length using plug press；
Using plug press main frame be four beam and four-post hydraulic machine pressing machines, be equipped with front and back liftable rollgang and
Liftable rotating roller, during undergauge operation:
By moved cross beam under main frame and roller-way coordination, find out the long axis direction of steel pipe oval cross section, and so that it is rotated
To vertical direction, send into necking down mould paragraph by paragraph, make deviation from circular from ＜ 0.3% under pressure；
Find out high point along steel pipe axis, and so that it is rotated to vertically upward, making high point be admitted to plug press
Immediately below upper mould, steel pipe falls on bearing, improves steel pipe linearity, reach design on plug press under molding pressure effect
Require.
The measurement of diameter is carried out in the Difference angles away from weld seam, respectively ± [8,30,60,90,120,150,
172]°；The circularity recording after undergauge is between 0.10%～0.15%.
8) quality examination: ultrasound investigation, x-ray inspection, pipe end magnetic particle inspection and visual examination；
9) water pressure test: steel pipe is carried out with 100% hydrostatic test, testing pressure for hydrostatic test is that the minimum surrender of steel pipe is strong
The 95%～100% of degree；
10) quality examination: ultrasound investigation, x-ray inspection, pipe end magnetic particle inspection and visual examination；
11) chamfered edge: the steel pipe checking qualified is carried out tube end maching.
Embodiment:
Using width be 1525mm, thickness be that the x65 controlled rolling steel plate of 25.4mm carries out the system of φ 508 longitudinal submerged arc welded pipe
Make.Step is as follows:
1) milling side, retaining wall on slope: two-sided milling is carried out to steel plate two edges by edge milling machines, makes up to the plate of requirement
Width, the edges of boards depth of parallelism and bevel shape.
2) pre-flanging: according to the technical requirement on design of steel pipe, using pre-flanging machine, edges of boards are bent to satisfactory song
Rate.
3) jco molding:
First, using jco forming machine, the half of the steel plate after pre-flanging is carried out Multi-step forming, be pressed into " j " shape；
By it, second half carries out same Multi-step forming again, is pressed into " c " shape；
The last middle pressing one-time in whole steel plate forms it into " o " shape of opening.
4) joint close and prewelding: by adjusting the position of joint close Prewelding machine pressure roller, make the bevel for welding of steel pipe after molding good
Coupling together it is ensured that misalignment, gap size meet design requirement, welded using gas shielded welding mode simultaneously.
5) weldering in: welded using four Lincoln weld bevel for weldings inside steel pipe, welding wire is jw-9z, first
Silk adopts DC reverse connection, and the second to four is exchange.Welding condition is: first electric current 950a, voltage 34v；Second
Electric current 950a, voltage 38v；3rd electric current 800a, voltage 38v；4th electric current 700a, voltage 40v；Distance between weldingwires be 18～
20mm, speed of welding is 150mm/min.
6) outside weld: welded using four Lincoln weld bevel for weldings outside steel pipe, welding wire is jw-9z, first
Silk adopts DC reverse connection, and the second to four is exchange.Welding condition is: first electric current 1100a, voltage 34v；Second
Electric current 750a, voltage 38v；3rd electric current 600a, voltage 40v；4th electric current 500a, voltage 42v；Distance between weldingwires be 18～
20mm, speed of welding is 175mm/min.
7) mechanical undergauge: after the completion of steel-pipe welding, using 1.0% fine pressure shrinkage, steel pipe total length is compressed, i.e. undergauge.
Undergauge is carried out by piecewise progressive manner, and after every second compression, the step-length of steel pipe axial movement is 600mm it is ensured that each compression walks
Enough laps between long terminal；Then physical dimension measurement and mechanics performance determining are carried out.
Roundness measurement: for Contrast on effect, the circularity before measuring undergauge and after undergauge.Straight with slide calliper rule and miking
Footpath, the measurement of diameter is carried out in the Difference angles away from weld seam, respectively ± [8,30,60,90,120,150,172] °, so
Calculate the difference of the maximum gauge recording and minimum diameter afterwards, then the percent obtaining divided by nominal diameter of steel pipe is steel pipe circle
Degree.Before undergauge, its circularity is about 0.6%.The circularity recording after undergauge is between 0.10%～0.15%.
8) quality examination: ultrasound investigation, x-ray inspection, pipe end magnetic particle inspection and visual examination.
Residual stress measurement: the mensure of residual stress is carried out on the pipe ring of 100mm length.First with saw, pipe ring is cut, from
Opening after incision can determine the residual stress of pipe.Undergauge makes 133mpa during residual stress amplitude reduction, never undergauge
It is decreased to 26mpa during undergauge 1.1%.
9) water pressure test: steel pipe is carried out with 100% hydrostatic test, testing pressure for hydrostatic test is that the minimum surrender of steel pipe is strong
The 95%～100% of degree；
10) quality examination: ultrasound investigation, x-ray inspection, pipe end magnetic particle inspection and visual examination；
11) chamfered edge: the steel pipe checking qualified is carried out tube end maching.
The deep water submerged-arc welding large-diameter steel pipe technical parameter applying manufacture of the present invention is shown in Table 1:
Physical dimension before and after table 1 steel pipe undergauge, material property and collapse pressure
Diameter reducing process significantly improves the elastic limit in outside, and makes the flex point of response curve become steeper, conquassation pressure
Power improves 45%.
Using having the beneficial effect that of present invention manufacture deep water submerged-arc welding large-diameter steel pipe:
(1) utilize plug press, ring compression is carried out so as to be locally deformed with to steel pipe total length, so that caliber is subtracted
Little, improve steel pipe sizes tolerance, be less than 0.5mm in the id tolerance of full length of tube scope, and circularity is less than 0.3%；
(2) pass through mechanical necking down, residual stress can be reduced, improve the linearity of steel pipe；
(3) pass through mechanical necking down, replace with compression by expanding, that is, improve the compression ratio in " o " stage for the steel pipe, or will be expanding
Rate is reduced to less than 1.0%, and cooling formation technic is optimised, and improves compression yield strength and the collapse pressure of steel pipe.
It should be noted that above-described embodiment is exemplary rather than limiting the present invention, those skilled in the art are possible to design very
Many alternate embodiments are without deviating from the right of this patent.
Claims (4)
1. a kind of deep water undergauge manufacture method of submerged-arc welding large-diameter steel pipe, including side, pre-flanging, jco molding, joint close and
Prewelding, interior weldering, outside weld, the water pressure test, to rib, ultrasound investigation, x-ray check processing step, concrete technology step is:
1) milling side, retaining wall on slope: two-sided milling is carried out to steel plate two edges by edge milling machines, makes up to plate width, the plate of requirement
The side depth of parallelism and bevel shape；
2) pre-flanging: required according to steel pipe curvature and caliber size requires, edges of boards are bent to meeting the requirements using pre-flanging machine
Curvature；
3) jco molding:
First, using jco forming machine, the half of the steel plate after pre-flanging is carried out Multi-step forming, be pressed into " j " shape；
By it, second half carries out same Multi-step forming again, is pressed into " c " shape；
The last middle pressing one-time in whole steel plate forms it into " o " shape of opening；
4) joint close and prewelding: by adjust joint close Prewelding machine pressure roller position, make the steel-pipe welding groove after molding good
Fit over together it is ensured that misalignment, gap size meet design requirement, welded using gas shielded welding mode simultaneously；
5) weldering in: welded using four Lincoln weld bevel for weldings inside steel pipe, first adopts DC reverse connection, the
Two to four is exchange；
6) outside weld: welded using four Lincoln weld bevel for weldings outside steel pipe, first adopts DC reverse connection, the
Two to four is exchange；
It is characterized in that:
7) mechanical undergauge: ring compression is carried out to steel pipe total length using plug press；
8) quality examination: ultrasound investigation, x-ray inspection, pipe end magnetic particle inspection and visual examination；
9) water pressure test: steel pipe is carried out with 100% hydrostatic test；
10) quality examination: ultrasound investigation, x-ray inspection, pipe end magnetic particle inspection and visual examination；
11) chamfered edge: the steel pipe checking qualified is carried out tube end maching.
2. the deep water undergauge manufacture method of submerged-arc welding large-diameter steel pipe according to claim 1, is characterized in that: described step
7) mechanical undergauge, the main frame using plug press is four beam and four-post hydraulic machine pressing machines, is equipped with liftable conveying roller in front and back
Road and liftable rotating roller, during undergauge operation:
By moved cross beam under main frame and roller-way coordination, find out the long axis direction of steel pipe oval cross section, and make its rotate to hang down
Nogata is to feeding necking down mould, makes deviation from circular from ＜ 0.3% under pressure paragraph by paragraph；
Find out high point along steel pipe axis, and so that it is rotated to vertically upward, making high point be admitted to mould on plug press
Underface, steel pipe falls on bearing, improves steel pipe linearity on plug press under molding pressure effect, and reaching design will
Ask.
3. the deep water undergauge manufacture method of submerged-arc welding large-diameter steel pipe according to claim 2, is characterized in that: described step
7) measurement of diameter is carried out in the Difference angles away from weld seam, respectively ± [8,30,60,90,120,150,172] °；Undergauge
The circularity recording afterwards is between 0.10%-0.15%.
4. the deep water undergauge manufacture method of submerged-arc welding large-diameter steel pipe according to claim 1, is characterized in that: described step
9) testing pressure for hydrostatic test is the 95%～100% of steel pipe SMYS.
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| CN105855671A (en) * | 2016-06-03 | 2016-08-17 | 合肥紫金钢管股份有限公司 | Butting process of large-diameter rolled steel pipe for building structure |
| CN108918285B (en) * | 2018-08-30 | 2024-03-19 | 番禺珠江钢管（珠海）有限公司 | Pipe section crushing device and test method thereof |
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| JP4811166B2 (en) * | 2006-07-24 | 2011-11-09 | Ｊｆｅスチール株式会社 | Manufacturing method of super high strength welded steel pipe exceeding tensile strength 800MPa |
| CN101205596B (en) * | 2007-12-10 | 2010-12-01 | 中国石油集团渤海石油装备制造有限公司 | Manufacture technique of X120 pipeline steel submerged arc straight weld pipe |
| CN102233389B (en) * | 2010-04-27 | 2015-09-02 | 辽阳钢管有限公司 | Size reducing machine |
| CN102310119B (en) * | 2011-09-02 | 2013-03-20 | 中国石油集团渤海石油装备制造有限公司 | Manufacturing method of X65 pipeline steel longitudinal submerged arc welded pipe for undersea use |
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